Number of permutations on n letters that have only cycles of length 4 or less.
A070945
Number of permutations on n letters that have only cycles of length 4 or less.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =24a(5) =96a(6) =456a(7) =2472a(8) =14736a(9) =92304a(10) =632736a(11) =4661856a(12) =36364032a(13) =297668736a(14) =2583425664a(15) =23550535296a(16) =224086162176
External references
- oeis: A070945